Valve-geae



UNlT @ad PATENT @FFlLE VALVE-GEAR OF STEAM-ENGINES.

Specification of Letters Patent No. 32,690, dated July 2, 1861.`

T0 all whom it may concern:

Be it known that l, ANDREW HARTUPEE, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a new and usefulImprovement in Lifters for Puppet-Valves of Steam-Engines; and l. dohereby declare the following to. be a full, clear, and exactdescriptionthereof, reference being had to the annexed drawings, forming part ofthis specification, in which- Figure l, is a perspective view of myimproved lifter detached from the engine. Fig. Q is a side view thereofas applied to a horizontal engine, neither of the valves being raised.Fig. 3 represents the lifter turned so as to raise one valve. Fig. arepresents the lifter partly turned showing its action on the point ofthe lever.

My improvement consists in connecting the lifters, for the puppet valvesof steam engines of such a shape that they will raise the levers of thevalves by rolling contact or nearly so thus not only saving friction andavoiding the wearing away of the lever and lifter, but by applying` theforce of the lifter at the commencement of the stroke to the end of vthelever instead of near its center, effecting a saving of power andincreasing the eflicieney of the engine.

To enable others skilled in the art to. make and use my improved lifter,l will proceed to describe its construction and operation.

In the drawings a is the shaft which earries the lifters Z), b. Eachengine -has two lifters ofthe same size and shape, one of which Y).works loose on the shaft a, and the other b, being fastened to theshaft works with it in the usual manner, in order to admit of thereverse motion necessaryto raise the lever of one of the said valvesat-one end of the cylinder, while the lever of one of the exhaust valvesis raised at the other end. ln the drawings one lifter and one pair ofvalves only are shown 'in each ligure and for the sake of illustrationFig. 2 may represent the valves and lifter on one side, and Fig. 3 thevalves and lifter on the other side of the cylinder of the steam engine.

c, c, are the levers to work the exhaust valves, and (l (Z the levers towork the said valves.

The engine is of the ordinary construction, as my improvement applicableto almost any kind of engine.

My improvement in liftcrs consists in forming them of the shape shown inFig. l, the upper surface or outline of the lifter being a uniform curveorv arc of a circle, the

vedge4 or tangential point of which, (midway from either end,) I placeeither exactly in the center or axis of the shaft a, which carries it,or near to the center, and within the circumference of the shaft a. Theadvantage of this arrangement will be seen, by reference to Fig. fl, tobe, that when the shaft (t turns so as to raise one arm of the lifterl), instead of the face of the lever being applied first to a point inthe lever, c, some distance from the extremity of th'e lever, the peintof the lever which rests on the curved surface of the lifter, near tothe shaft (which is the center of motion), first receives the force ofthe lifter, and as the lifter rises, instead of rubbing along the underside of the lever it raises it to the point shown in Fig. 3, by rollingcontact or nearly so, thus very materially diminishing the friction,saving power and causing the engine to work more smoothly as the leversare raised with less of a jerk. In lifters as ordinarily constructed thelifter exerts less power on the lever to raise the valve at the momentwhen it begins to rise, than afterward, while the reverse should be thecase, as the greatest force needed just when the valve is first raised.And this l eect by my improvement which raises the levers from thepoint, while the ordinary lifters raise them at some distance from theirextrelnity. My invention thus. renders the valves equal in eiliciencyand easy of operation to balance valves, so that by the use of them theengineer has much greater control of hisengine, than with lifters ofother constructions.

Having thus described my improvement what l claim as my invention anddesire to secure by Letters Patent is,

The use of lifters for puppet valves of steam engines so constructed andarranged in relation to the shaft on which they are placed and by whichthey are operated, as

that their extremities shall. be inthe line of :1u nrc of u circle thetangential point of which, where it intersects Suid shaft, shall passwithin the circumference of the shaft, und either through its axis ornear thereto, for the purpose hereinbefore set forth.

In testimony whereof I have hereunto set my hand this fifth day' ofAugust A. D. 185C.

ANDREV I-IARTUPEE.

Titnessesz /V. DUDLEY KING, AND. MCMASTER.

